• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.1.1-1.6
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• 2015

The restoration of extensive zygomatic complex defects is a surgical challenge owing to the difficulty of accurately restoring the normal anatomy, symmetry, proper facial projection and facial width. In the present study, an extensive post-traumatic zygomatic bone defect was reconstructed using a custom-made implant that was made with a selective laser melting (SLM) technique. The computer-designed implant had the proper geometry and fit perfectly into the defect without requiring any intraoperative adjustments. A one-year follow-up revealed a stable outcome with no complications.

• Archives of Craniofacial Surgery
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• v.17 no.2
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• pp.45-50
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• 2016

Extensive surgical resection of the aerodigestive track can result in a large and complex defect of the oropharynx, which represents a significant reconstructive challenge for the plastic surgery. Development of microsurgical techniques has allowed for free flap reconstruction of oropharyngeal defects, with superior outcomes as well as decreases in postoperative complications. The reconstructive goals for oral and oropharyngeal defects are to restore the anatomy, to maintain continuity of the intraoral surface and oropharynx, to protect vital structures such as carotid arteries, to cover exposed portions of internal organs in preparation for adjuvant radiation, and to preserve complex functions of the oral cavity and oropharynx. Oral and oropharyngeal cancers should be treated with consideration of functional recovery. Multidisciplinary treatment strategies are necessary for maximizing disease control and preserving the natural form and function of the oropharynx.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.26 no.4
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• pp.263-279
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• 2022

This paper presents an automatic inspection of defects in semiconductor images. We devise a statistical method to find defects on homogeneous background from the observation that it has a log-normal distribution. If computer aided design (CAD) data is available, we use it to construct a signed distance function (SDF) and change the pixel values so that the average of pixel values along the level curve of the SDF is zero, so that the image has a homogeneous background. In the absence of CAD data, we devise a hybrid method consisting of a model-based algorithm and two neural networks. The model-based algorithm uses the first right singular vector to determine whether the image has a linear or complex structure. For an image with a linear structure, we remove the structure using the rank 1 approximation so that it has a homogeneous background. An image with a complex structure is inspected by two neural networks. We provide results of numerical experiments for the proposed methods.

• Bulletin of the Korean Mathematical Society
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• v.57 no.5
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• pp.1195-1204
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• 2020

In this paper we consider the holomorphic curves (or derived holomorphic curves introduced by Toda in [15]) with maximal defect sum in the complex plane. Some well-known theorems on meromorphic functions of finite order with maximal sum of defects are extended to holomorphic curves in projective space.

• Journal of Chest Surgery
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• v.16 no.1
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• pp.18-29
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• 1983

Thirty-two patients with a cyanotic cardiac malformations having more complex intracardiac defects than ones in a tetralogy of Fallot underwent complete intracardiac repairs in a-full-year period from July 1981 to June 1982. Twenty-two patients [68.8%] died within 30 days after surgery: Transposition of the great arteries, seven of 10 patients; Double-outlet right ventricle, four of 6 patients; Tricuspid atresia, four of 6 patients; Single ventricle, all of 4 patients; Pulmonary atresia, two of 3 patients; Double-outlet left ventricle, none of 2 patients; and Truncus arteriosus, one of a single patient. All deaths occurred with a low cardiac output syndrome or a failed off-bypass, and they were almost always accompanied with other grave postoperative complications. The complex intracardiac anatomy itself was one of the risk factors by making a complete intracardiac repair of the defects difficult in a small heart. The reconstruction of the right ventricular outflow carried a difficulty in balancing an adequate relief of the obstruction with an avoidance of making too much pulmonary valvular insufficiency as well. On the other hand, the presence of an elevated pulmonary arterial pressure and a high pulmonary vascular resistance was also the factors affecting the postoperative surviv als. The importance of detailed knowledge of intracardiac anatomy and hemodynamics from the careful preoperative evaluation of the patient was discussed along with the necessity of technical refinement of the correction.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.2
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• pp.55-63
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• 2014

Fractures and wrinkles are two major defects frequently found in the sheet metal forming process. The process has several noise factors that cannot be ignored when determining the optimal process conditions. Therefore, without any countermeasures against noise, attempts to reduce defects through optimal design methods have often led to failure. In this study, a new and robust design methodology that can reduce the possibility of formation of fractures and wrinkles is presented using decision-making theory. A two-attribute value function is presented to form the design metric for the sheet metal forming process. A modified complex method is adopted to isolate the optimal robust design variables. One of the major limitations of the traditional robust design methodology, which is based on an orthogonal array experiment, is that the values of the optimal design variables have to coincide with one of the experimental levels. As this restriction is eliminated in the complex method, a better solution can be expected. The procedure of the proposed method is illustrated through a robust design of the sheet metal forming process of a side member of an automobile body.

• Archives of Reconstructive Microsurgery
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• v.9 no.1
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• pp.75-79
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• 2000

The foot plays a vital role in standing and gait. This function results from harmonious interaction of bones, joints, and soft tissue. An imbalance or a defect in such structures can lead to impaired function of the foot. The mid foot, composed of cunieforms, navicular and cuboid bone, plays a vital role in maintaining longitudinal and transverse arches and injury or defects to this region can cause instability of the foot. This paper reports a case of complex foot injury; soft tissue defect of dorsum of foot, and medial and intermediate cuneiform bone defect, reconstructed in a single stage using vascularized osteocutaneous fibular free flap. Segmented to fit the defects of medial and intermediate cuneiform bones and a skin paddle providing adequate coverage, restored the stability to the arches and function of the midfoot. The fibula osteocutaneous free flap has appealing characteristics for reconstruction of the foot and the complex mid foot injuries can be considered to the long list of indications.

• Transactions of Materials Processing
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• v.21 no.8
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• pp.473-478
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• 2012

The yoke, a component of conventional motor-driven power steering system, often contains welding defects from its manufacturing process. To eliminate these defects, the precision cold forging process has been tried. In this study, the double-action complex forging has been used to manufacture a torsion joint yoke. The backward extrusion proved faster than the forward extrusion in forging of the product. The double-action complex forging process utilized an upper die composed of a punch, a punch guide, a disc spring and a coil spring. The forged material pushes up the punch guide, and then the disc spring and the coil spring balances the backward extrusion force. Consequently, the flow of material was essentially in the forward direction, resulting in a successful forging operation. The forging load of Al 6061-T6 was higher than that of the automotive structural hot rolled plate.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.2
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• pp.1-12
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• 2023

To make semiconductor chips, a number of complex semiconductor manufacturing processes are required. Semiconductor chips that have undergone complex processes are subjected to EDS(Electrical Die Sorting) tests to check product quality, and a wafer bin map reflecting the information about the normal and defective chips is created. Defective chips found in the wafer bin map form various patterns, which are called defective patterns, and the defective patterns are a very important clue in determining the cause of defects in the process and design of semiconductors. Therefore, it is desired to automatically and quickly detect defective patterns in the field, and various methods have been proposed to detect defective patterns. Existing methods have considered simple, complex, and new defect patterns, but they had the disadvantage of being unable to provide field engineers the evidence of classification results through deep learning. It is necessary to supplement this and provide detailed information on the size, location, and patterns of the defects. In this paper, we propose an anomaly detection framework that can be explained through FCDD(Fully Convolutional Data Description) trained only with normal data to provide field engineers with details such as detection results of abnormal defect patterns, defect size, and location of defect patterns on wafer bin map. The results are analyzed using open dataset, providing prominent results of the proposed anomaly detection framework.

• Archives of Reconstructive Microsurgery
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• v.7 no.1
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• pp.41-46
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• 1998

Microvascular free tissue transfer technique is widely accepted for reconstruction of extensive soft tissue defects on the extremities. The system of flap based on the subscapular artery and vein provides the widest ways of composite free flaps. The possible flaps that can be harvested based on this single vascular pedicle include the scapular and parascapular skin flaps, the serratus anterior and latissimus dorsi muscular flaps, the lateral scapular bone flap, the latissimus dorsi-rib flap, and the serratus anterior-rib flap. This combined flap is available to mutiple tissue defects or complex defects because it can incorporated with skin, muscle and bone flaps. A strikig advantage is the independent vascular pedicles of each components, which allow freedom in orientation of each components. So, it can be freely applied to any forms of three demensional defects on the upper and lower extremities. The combination of scapular cutaneous flap and latissimus dorsi musculocutaneous flap can be resurfaced for massive cutaneous defects on the extremities. We report the use of the combined scapular and latissimus dorsi free flap in seven patients to reconstruct massive deefcts on the extremities. There was no flap failure and little complications and disadvantages. The anatomy of this flap is reviewed and the indication and advantages are discussed.